avisynth: Cast to the right type when loading avisynth library functions
[libav.git] / libswscale / swscale.h
1 /*
2 * Copyright (C) 2001-2003 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This file is part of Libav.
5 *
6 * Libav is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * Libav is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with Libav; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #ifndef SWSCALE_SWSCALE_H
22 #define SWSCALE_SWSCALE_H
23
24 /**
25 * @file
26 * @ingroup libsws
27 * @brief
28 * external api for the swscale stuff
29 */
30
31 #include <stdint.h>
32
33 #include "libavutil/avutil.h"
34 #include "libavutil/log.h"
35 #include "libavutil/pixfmt.h"
36 #include "version.h"
37
38 /**
39 * @defgroup libsws Color conversion and scaling
40 * @{
41 *
42 * Return the LIBSWSCALE_VERSION_INT constant.
43 */
44 unsigned swscale_version(void);
45
46 /**
47 * Return the libswscale build-time configuration.
48 */
49 const char *swscale_configuration(void);
50
51 /**
52 * Return the libswscale license.
53 */
54 const char *swscale_license(void);
55
56 /* values for the flags, the stuff on the command line is different */
57 #define SWS_FAST_BILINEAR 1
58 #define SWS_BILINEAR 2
59 #define SWS_BICUBIC 4
60 #define SWS_X 8
61 #define SWS_POINT 0x10
62 #define SWS_AREA 0x20
63 #define SWS_BICUBLIN 0x40
64 #define SWS_GAUSS 0x80
65 #define SWS_SINC 0x100
66 #define SWS_LANCZOS 0x200
67 #define SWS_SPLINE 0x400
68
69 #define SWS_SRC_V_CHR_DROP_MASK 0x30000
70 #define SWS_SRC_V_CHR_DROP_SHIFT 16
71
72 #define SWS_PARAM_DEFAULT 123456
73
74 #define SWS_PRINT_INFO 0x1000
75
76 //the following 3 flags are not completely implemented
77 //internal chrominance subsampling info
78 #define SWS_FULL_CHR_H_INT 0x2000
79 //input subsampling info
80 #define SWS_FULL_CHR_H_INP 0x4000
81 #define SWS_DIRECT_BGR 0x8000
82 #define SWS_ACCURATE_RND 0x40000
83 #define SWS_BITEXACT 0x80000
84
85 #define SWS_MAX_REDUCE_CUTOFF 0.002
86
87 #define SWS_CS_ITU709 1
88 #define SWS_CS_FCC 4
89 #define SWS_CS_ITU601 5
90 #define SWS_CS_ITU624 5
91 #define SWS_CS_SMPTE170M 5
92 #define SWS_CS_SMPTE240M 7
93 #define SWS_CS_DEFAULT 5
94
95 /**
96 * Return a pointer to yuv<->rgb coefficients for the given colorspace
97 * suitable for sws_setColorspaceDetails().
98 *
99 * @param colorspace One of the SWS_CS_* macros. If invalid,
100 * SWS_CS_DEFAULT is used.
101 */
102 const int *sws_getCoefficients(int colorspace);
103
104 // when used for filters they must have an odd number of elements
105 // coeffs cannot be shared between vectors
106 typedef struct SwsVector {
107 double *coeff; ///< pointer to the list of coefficients
108 int length; ///< number of coefficients in the vector
109 } SwsVector;
110
111 // vectors can be shared
112 typedef struct SwsFilter {
113 SwsVector *lumH;
114 SwsVector *lumV;
115 SwsVector *chrH;
116 SwsVector *chrV;
117 } SwsFilter;
118
119 struct SwsContext;
120
121 /**
122 * Return a positive value if pix_fmt is a supported input format, 0
123 * otherwise.
124 */
125 int sws_isSupportedInput(enum AVPixelFormat pix_fmt);
126
127 /**
128 * Return a positive value if pix_fmt is a supported output format, 0
129 * otherwise.
130 */
131 int sws_isSupportedOutput(enum AVPixelFormat pix_fmt);
132
133 /**
134 * @param[in] pix_fmt the pixel format
135 * @return a positive value if an endianness conversion for pix_fmt is
136 * supported, 0 otherwise.
137 */
138 int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt);
139
140 /**
141 * Allocate an empty SwsContext. This must be filled and passed to
142 * sws_init_context(). For filling see AVOptions, options.c and
143 * sws_setColorspaceDetails().
144 */
145 struct SwsContext *sws_alloc_context(void);
146
147 /**
148 * Initialize the swscaler context sws_context.
149 *
150 * @return zero or positive value on success, a negative value on
151 * error
152 */
153 int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter);
154
155 /**
156 * Free the swscaler context swsContext.
157 * If swsContext is NULL, then does nothing.
158 */
159 void sws_freeContext(struct SwsContext *swsContext);
160
161 /**
162 * Allocate and return an SwsContext. You need it to perform
163 * scaling/conversion operations using sws_scale().
164 *
165 * @param srcW the width of the source image
166 * @param srcH the height of the source image
167 * @param srcFormat the source image format
168 * @param dstW the width of the destination image
169 * @param dstH the height of the destination image
170 * @param dstFormat the destination image format
171 * @param flags specify which algorithm and options to use for rescaling
172 * @return a pointer to an allocated context, or NULL in case of error
173 * @note this function is to be removed after a saner alternative is
174 * written
175 */
176 struct SwsContext *sws_getContext(int srcW, int srcH, enum AVPixelFormat srcFormat,
177 int dstW, int dstH, enum AVPixelFormat dstFormat,
178 int flags, SwsFilter *srcFilter,
179 SwsFilter *dstFilter, const double *param);
180
181 /**
182 * Scale the image slice in srcSlice and put the resulting scaled
183 * slice in the image in dst. A slice is a sequence of consecutive
184 * rows in an image.
185 *
186 * Slices have to be provided in sequential order, either in
187 * top-bottom or bottom-top order. If slices are provided in
188 * non-sequential order the behavior of the function is undefined.
189 *
190 * @param c the scaling context previously created with
191 * sws_getContext()
192 * @param srcSlice the array containing the pointers to the planes of
193 * the source slice
194 * @param srcStride the array containing the strides for each plane of
195 * the source image
196 * @param srcSliceY the position in the source image of the slice to
197 * process, that is the number (counted starting from
198 * zero) in the image of the first row of the slice
199 * @param srcSliceH the height of the source slice, that is the number
200 * of rows in the slice
201 * @param dst the array containing the pointers to the planes of
202 * the destination image
203 * @param dstStride the array containing the strides for each plane of
204 * the destination image
205 * @return the height of the output slice
206 */
207 int sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[],
208 const int srcStride[], int srcSliceY, int srcSliceH,
209 uint8_t *const dst[], const int dstStride[]);
210
211 /**
212 * @param inv_table the yuv2rgb coefficients, normally ff_yuv2rgb_coeffs[x]
213 * @return -1 if not supported
214 */
215 int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4],
216 int srcRange, const int table[4], int dstRange,
217 int brightness, int contrast, int saturation);
218
219 /**
220 * @return -1 if not supported
221 */
222 int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table,
223 int *srcRange, int **table, int *dstRange,
224 int *brightness, int *contrast, int *saturation);
225
226 /**
227 * Allocate and return an uninitialized vector with length coefficients.
228 */
229 SwsVector *sws_allocVec(int length);
230
231 /**
232 * Return a normalized Gaussian curve used to filter stuff
233 * quality = 3 is high quality, lower is lower quality.
234 */
235 SwsVector *sws_getGaussianVec(double variance, double quality);
236
237 /**
238 * Allocate and return a vector with length coefficients, all
239 * with the same value c.
240 */
241 SwsVector *sws_getConstVec(double c, int length);
242
243 /**
244 * Allocate and return a vector with just one coefficient, with
245 * value 1.0.
246 */
247 SwsVector *sws_getIdentityVec(void);
248
249 /**
250 * Scale all the coefficients of a by the scalar value.
251 */
252 void sws_scaleVec(SwsVector *a, double scalar);
253
254 /**
255 * Scale all the coefficients of a so that their sum equals height.
256 */
257 void sws_normalizeVec(SwsVector *a, double height);
258 void sws_convVec(SwsVector *a, SwsVector *b);
259 void sws_addVec(SwsVector *a, SwsVector *b);
260 void sws_subVec(SwsVector *a, SwsVector *b);
261 void sws_shiftVec(SwsVector *a, int shift);
262
263 /**
264 * Allocate and return a clone of the vector a, that is a vector
265 * with the same coefficients as a.
266 */
267 SwsVector *sws_cloneVec(SwsVector *a);
268
269 /**
270 * Print with av_log() a textual representation of the vector a
271 * if log_level <= av_log_level.
272 */
273 void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level);
274
275 void sws_freeVec(SwsVector *a);
276
277 SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
278 float lumaSharpen, float chromaSharpen,
279 float chromaHShift, float chromaVShift,
280 int verbose);
281 void sws_freeFilter(SwsFilter *filter);
282
283 /**
284 * Check if context can be reused, otherwise reallocate a new one.
285 *
286 * If context is NULL, just calls sws_getContext() to get a new
287 * context. Otherwise, checks if the parameters are the ones already
288 * saved in context. If that is the case, returns the current
289 * context. Otherwise, frees context and gets a new context with
290 * the new parameters.
291 *
292 * Be warned that srcFilter and dstFilter are not checked, they
293 * are assumed to remain the same.
294 */
295 struct SwsContext *sws_getCachedContext(struct SwsContext *context,
296 int srcW, int srcH, enum AVPixelFormat srcFormat,
297 int dstW, int dstH, enum AVPixelFormat dstFormat,
298 int flags, SwsFilter *srcFilter,
299 SwsFilter *dstFilter, const double *param);
300
301 /**
302 * Convert an 8-bit paletted frame into a frame with a color depth of 32 bits.
303 *
304 * The output frame will have the same packed format as the palette.
305 *
306 * @param src source frame buffer
307 * @param dst destination frame buffer
308 * @param num_pixels number of pixels to convert
309 * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
310 */
311 void sws_convertPalette8ToPacked32(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
312
313 /**
314 * Convert an 8-bit paletted frame into a frame with a color depth of 24 bits.
315 *
316 * With the palette format "ABCD", the destination frame ends up with the format "ABC".
317 *
318 * @param src source frame buffer
319 * @param dst destination frame buffer
320 * @param num_pixels number of pixels to convert
321 * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
322 */
323 void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
324
325 /**
326 * Get the AVClass for swsContext. It can be used in combination with
327 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
328 *
329 * @see av_opt_find().
330 */
331 const AVClass *sws_get_class(void);
332
333 /**
334 * @}
335 */
336
337 #endif /* SWSCALE_SWSCALE_H */